Relationship between occlusal force and morphology in the mandibular molar region using a dental cone beam CT

Abstract

We examined the effect of occlusal force on morphology of the mandibular molar region. The subjects were 20 males with individual normal occlusion. The bite force was measured with an occlusal force-meter using pressure sensitive film. The morphology of the mandibular molar region was determined with dental cone beam CT. Slice images across the apex of mesial root of the mandibular first molar were used to measure of (1) the widths of the mandibular molar region across the apex, (2) the widths of the mandibular molar region at the midpoint between the apex and the nadir of the mandibular bone, (3) the widths of the cortical bone in the mandibular molar region across the apex, (4) the widths of the mandibular cortical bone at the midpoint between the apex and nadir of the mandibular bone, (5) the distance between the apex and the lingual cortical bone surface, and (6) the distance between the apex and the buccal cortical bone surface. Correlation analysis was conducted between the occlusal force and these measurements. We investigated the positive correlation between occlusal force and the FH-plane-based width of the mandibular bone across the apex and the width of the mandibular bone at the midpoint between the apex and nadir of the mandibular bone. We found that the mandibular inter molar width increased with increases in occlusal force.